Pneumatic nail-driver.



S. B. STEWART. PNEUMATIG NAIL DRIVER.'

APPLICATION FILED JULY 10l 1906.

S. B. STEWART.

PNEUMATIC NAIL DRIVER.

APPLIGATION FILED JULY 1o, 1906.

902,620. Patented Nov. 3, 1908.

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S. B. STEWART.

PNEUMATIG NAIL DRIVER.

APPLICATION FILED JULY 10l 1906. v

Patented Nov. 3, 1908.

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um 1x \I R am n M Mio?? SCOTT B. STEWART, OF AUGUSTA, MAINE.

PNEUMATIC NAIL-DRIVER.

Speeication of Letters Patent.

Patented Nov. 3, 1968.

Application filed July 10, 1906. Serial No. 325,509.

To all 'whom it may concern:

Be it known that 1, SCOTT B. STEWART, a

resident of Augusta, in the county of Kennebec and State of Maine, haveinvented certain new and useful Improvements in Pneumatic Nail-Drivers;and I do hereby declare the following to be a full, clear, and exactdescription of the invention, such as will enable others skilled in theart to which it appertains to mal-e and use the same.

My invention relates to improvements in pneumatic nail drivers, theobject of the invention being to provide improved means for feeding thenails into positlon in advance of a pneumatic hammer to drive them, andthe invention consists in certain novel features of construction andcombinations and arrangements of parts as will be more fully hereinafterdescribed and pointed out in the claims.

In the accompanying drawings, Figure 1 is a view in side elevationillustrating my improvements. Fig. 2 is a top plan view. Fig. 3 is anend elevation. Fig. 4 is a view in longitudinal section, and Fig. 5 isan enlarged view in longitudinal section of the nose portion of theapparatus.

1, 1, represent parallel rods, having pistons 2, 2, thereon, andconnected at their rear ends, by a cross bar 3, and at their forwardends, these rods 1, 1, are secured to the cross head 4 on the noseportion 5 of the machine or apparatus.

Mounted on the pistons 2, 2, are cylinders 6, 6, carrying the hammer 7,and movable on the pistons by the pressure of air or other fluid, aswill more fully hf-reinafter appear. The rear portion of the hammer isprovided with a head 7 l disposed in the space 7 b between the cylinders6, 6, and at respective ends of the space 7b, cushions 7 e, 7 d arelocated so as to engage the head 7. The space 7b is longer than the head7 a so that the cylinders will move a short distance before the head 7'lis engaged by the cushion 7 C, and hence there will be a hammer actionbetween the driving cylinders and the head 7El ofthe hammer 7. Theforward end of the hammer 7 is movable in a guide channel 8 in the nose5, and carries a contracted nail driving plunger 9 at its forward end,movable in a channel or throat 10 in the nose.

The nose portion of the machine, which is shown in section, in Fig. 5,is provided with a passage 11, having ,a nipple 12 at -ts'outer end, forthe attachment of an air tube or hose 13 for forcing the nails, by thecurrent of air, into the passage 11. T he internal diameter of this tube13 is just sufficient to permit the free assage of one nail at a time,the point of tlle rear nail resting against the head of the nail infront, and the nails are prevented from any retrograde movement by meansof catches or dogs in the tube.

In the upper portion of passage 11, isa dog 14, pivoted between itsends, and provided with a spring 15 exerting downward pressure on thisend of the dog, and the forward end of the dog is held depressed by aplunger 16, which also extends across the passage 11 and prevents themovement of a nail into channel 1() in front of plunger 9, until the proer time. The plunger 16 also serves as a va ve to close communicationbetween the channel 11 and the throat 10. The upper end of the plunger16 is connected with a pivoted arm 17, the latter being connected at itsfree end -to the end of a stem 18 on a piston 19. Piston 19 is locatedin a chamber in the nose'5, and an air duct 20 communicates with thebottom of this chamber.

A three-way valve 21 is located in the duct or passage 20, and a smallpipe 22 connects the duct 20 with a nozzle or cou ling 26, so that whenthe valve 21 is opene by mechanism to be hereinafter explained, air willow from said nozzle or cou ling, through pipe 22 raise piston 19 and punger 16, and w en the valve is returned to its former pov sition, aspring 23 will depress plunger 16 and piston 19 and eject the air belowpiston 19 through an exhaust port 24 with which the three-way valve 21communicates.

The air from passage 11 esca es through a grating 25 in said passage to51e nozzle 26, the latter being connected by a hose 27 with a nozzle 28on an air chamber 29 at the cylinder end of the machine, and this airchamber 29 is connected by small ipes 30 with cylinders 6, 6, to directthe air tiiereinto between the ends of the cylinders being pistons 2, 2,to drive the hammer forward.` A valve 31, similar to valve 21, islocated in air chamber 29 to control the passage of air to thecylinders, and this valve 31, and the valve 21, are controlled by a tripframe 32, which will now be explained.

The trip frame 32 'is mounted to slide in suitable guides 33 on themachine, and .is provided at its forward end with an angular ring Inanail driving machine the combina- 34 in advance of the discharge end ofthe nose 5, and is normally held projected forward by springs 34a.

A bar 35 is secured to the rear end of the machine, extends beneath thesame, and has a handle 353L secured thereto, and a strap or band 37 maybe passed around this bar 35 and the operators arm or body, to assisthim in roperly holding the machine.

en the machine is placed in position for operation and the angular ring34 pressed against the place where a nail is to be driven, the tripframe 32 will be forced rearward (or the machine proper moved forward)to compel a .catch 38 on a spring arm of the trip frame, to engage atrip arm 39 on valve 21, and a catch 40 on a spring arm of said frame 32to engage a trip arm 41 on valve 31, and open both valves. Air willraise piston '19 and plunger 16, to permit a Anail to be moved forwardinto channel or throat 10, and the rear end of dog 14 will engage thehead of the next nail and prevent its forward movement. A lug 42 willengage another arm 43 on valve 21 to shut off the passage of air to thepiston 19, permitting the piston-v and plunger 16 to be forced down bythe spring 23 to compel the Iparts in the nose to assume their formerposltions. The hammer will be o erated by the air to drive the nail inchanne or throat 10,'

and as the hammer reaches its forward end of stroke, an arm 45 on valve31 (which valve will be carried forward with the cylinders 6 withoutmoving the frame 32) will strike a shoulder 44 on trip frame 32 andeffect a closing of said valve 31. Springs 46 will return the hammer toits former set osition.

When the hammer is removed) from the work, the s ring arms having thecatchers 35 and 40 wi in the downward movement of the ,frame 32, snaplover the ends of trip arms 39 and 41 respectively, the trip arms beingheld against movement by stops.

A great many slight changes might be made in the general form andarrangement of the parts described without departing from my invention,and hence, I do not restrict myself to the precise details set forth butconsider myself at liberty to make such slight changes and alterationsas fairly fall within the s irit and scope of my invention.

Having fu ly described my invention, what I claim as new and desire tosecure by Letters-Patent is 1. In a nail driving machine, thecombination with a hammer and a member having a feed channel, of aplunger for obstructing said channel, means for moving said plunger topermit the passage of a nail, a pivoted device movable in one directionby the plunger, and means for moving saidpivoted device in the otherdirection to engage the head of a lnail when the plunger is moved tounobstruct the feed channel.

feed channel, of a plunger for obstructing the feed channel, a pneumaticdevice connected with the plunger for moving it in a direction tounobstruct the feed channel, a spring for moving the plunger in theother direction, a dog pivoted between its ends behind said plunger andhaving one end yconnected with said plunger, and a spring for moving theother end of said dog into the feed channel when the plunger is moved tounobstruct the latter.

4. In an apparatus of the character described, the combination with apneumatic hammer, and pneumatically-operated means for feeding nails toa point in front of the hammer, a valve for the pneumatic hammer and avalve for the feeding means, ofan actudisconnected therefrom, and'contact devices cn said actuator and valves for trippin the latter intimed relation to effect the fee and driving of a nail, substantially asdescribed.

5. In an apparatus of the character de scribed, the combination with ahammer, of a nose portion in which the hammer plunger moves, a nailchannel directing nails through the nose to a point in front of the`plunger, a pivoted dog in said channel, a plunger across. 'the channelclosing the same and holding the dog out of the way of the nails, saiddog moving into the path of nail heads when the plunger is raised torelease the first nail, and pneumatic means for operating the plungerand the hammer.

6. In an apparatus of the character described, the combination with apneumatic hammer, and a valve for regulating the passage of air thereto,of pneumatic feeding means for directing nails in position in front ofthe hammer, a valve for regulating lthe passage ofair to operate thefeeding means, an actuator frame movable on the apparatus, and deviceson the actuator frame to move the said valves, but normally disconnectedtherefrom.

7. In a machine of the character described, the combination with apneumatic hammer, and a valve for regulating the passage of air thereto,of pneumatic feeding means for directing nails in position in front ofthe hamtion with a hammer and a member having a ator common to saidvalves but normally nier, a valve for regulating the passage of air Intestimony whereof, I have signed this to operate the feeding means, anactuator speciicationin the presence 0f two subscribfranie movable onthe machinefrarne and ing witnesses.

SCOTT vB. STEWART. Witnesses:

projecting beyond thefo'rward end thereof,

and devices on the actuator lframe to .move v said valves but normallydisconnected there- LEWIS SELBING, from. Mrs. S. A. BARNES.

